pls help
will give the brainliest!
Need explanation
Urgent​
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Answer:
[tex] a=\pm 4[/tex]
Step-by-step explanation:
[tex] M^2= \begin{bmatrix} a^2 +1 & 0 \\ 0 & a^2+1 \end{bmatrix} =17 \begin{bmatrix} 1 & 0 \\ 0 & 1 \end{bmatrix}\\[/tex]
Equate the terms to get:
$a^2+1=17$
$\implies a^2=16 \implies a= \pm 4$